Mining machine



J. C. SPROUL MINING MACHINE May Ti, 1951 Filed July 10, 1946 .mIMIVEIIlll-l lNvam-ora John Con nel Sproul P441 aw-1L -9 ATTY Patented May l, 1951 UNITED PATEN T 0F F .liC E1 John Connel-sproul, Glasgow, Scotland,.assignor to Mavor & lCoulson, Limited, Glasgow, Scotland Application July 120,, 1946, Serial No. 682,566 In'Great Britain Jun'e S, 1944 oarrying chain adaptedto make a cut in the-coal seam in .a vertical plane extending in thedirection of advance of the machine. Such cutters makea cut theheightof which corresponds-With the distance vertically between the highest and lowest limits of the chain circuit.

The object of this invention is to provide a Shearing cutter which is made adjustable so that the workers will be enabled to vary the vertical distance between the upper and lower limits, while maintaining the length of the chain path constant.

More specifically, the object of the invention is to provide for making the described variation in height, firstly, without need for adjusting the usual device for regulating the tension :ef the cutter chain and, secondly, without affecting the working relationship between the bottom of the chain circuit and the bottom of the coal seam.

Therefore the invention comprises a shearing cutter of. the cutter chain type having a chainguiding frame made up of a lower longitudinalelement which is fixed to the mining machine, an upper longitudinal element which is raised or lowered to vary the height of cutand a front linkage which interconnects said longitudinal. elements, and adjustmentmeansfor raising or'lowering said. upper longitudinal element througha range .of positions and moving said linkage to neutralise any alteration in the length of the chain path due to the raising .or lowering.

.An example of a shearing cutter in accordance with the invention is illustrated in the accom-- panying drawing, in which:

Figure 1 is an elevation, and Figure-2 isa-section on the line II-II .of Figure 1.

The shearing cutter is carried by the body .of the mining machine, designated M, and comprises a cutter-chain-guiding frame which is made up of four elements disposed .in a vertical plane, viz. two long upper and lower longitudinal elements A and B and two short link element 0 and -D at the forward end. The longitudinal elements A and B are pivotally connected at their rear ends by a horizontal transverse pivot pin 5. At their forward ends the longitudinal elements A andB are connected by the two link elements C and D which constitute a toggle linkage between the longitudinal elements. The longitudinal elements diverge in the forward. direction sothat the frame is of greater height at the forward end; bending of the toggle linkage provides for variation of this divergence and thusef the height of theframe. The toggle linkage-is bent forward except in the position of maximum height where the linkage is straight and vertical. The usual driving sprocket wheel 2 for the cutter chain is mounted on the body M of the mining machine at a position to-the rear of the The driving sprocket wheel '2 and the pivot. I- frame elements A, .B, :LCQD provide for the guidance of the endless "cutter chain (not shown) the path of which is indicated by the dot-dash line .6 :in Figure l. The elements A, B, and- D form .a. channel guide-way 6a for the chain. Thus, it will be evident thatthese four elements A,.B, C and Dconstituting the frame individual-1y form parts :of an endless path of guidance for thecutterchain 6.

In Figure 2 the coal face isi-ndicatedat E, and

in Figure l the line F indicates the bottom of tive rows of holes are slightly different so that two'holes of each row coincidein each-of a range of positions into which the block T can be adjusted. A pin I'll passed through those holes which coincide for a given height of cut serves to lock the block in its positionof adjustment. A strut H is pivoted at its front end to the "element D and extends backwards sotha-t its rear" end. is slida'ble on the frame element Bandi's adapted to come against the block 1, whichserves as anabutment.

Byadjustin'gthe position of theabutment block Lin the channeled element B, thea-ngular relationship of the elementsC and D-can Joe-adjusted to limit the degree of straightening of the togglelinkage to the height required when the cutter is thrust into the coal. It will be seen that if the elements A and Bare closedmoreor less to reduce the cutting height, the elements C and D are-bent forwards, their angular relationship becoming less obtuse, to'neutralize any-shortening usual device for regulating the tension of the cutter chain. As shown, the device includes an adjustment screw 12 which is journalled in a bar 13 secured between the sides of the lower element B and which is threaded through a nut l4 secured to the machine body M. By virtue of this screw and nut device, the lower element B (although normally a rigid fixture on the machine body) is adjustable lengthwise to regulate the tension of the cutter chain. Pin [5 screwed into the body M through slots 16 in the lower element B serve to secure the element B in its position of adjustment as a rigid fixture on the machine body M. The bar 13 serves also to assist in constraining the upper element A to its co-planar relationship with the element B.

It will be noted that throughout the range of adjustment of the frame elements A, C, and D, the relationship between the lower flight of the chain path 6 and the bottom F of the coal seam remains unchanged by virtue of the fixation between the lower element B and the machine body M.

Moreover, by virtue of the neutralising action of the toggle link elements C and D when the cutting height is varied, there is no need for the comparatively laborious task of adjusting the tension-regulating device [2, 13, which device is usually adjusted only if the cutter chain requires tightening before the machine is brought into position for coal-cutting operations.

In operation of the shearing cutter, when the chain-guiding frame is advanced into the coal, the backward reactionary thrust thereof tends to straighten the toggle linkage C, D until the slidable end of the strut ll abuts against the block 1 (which is already adjusted to suit the height of the cut) whereupon the linkage is held fast. On the other hand, when the cutter is withdrawn from the coal, the toggle linkage will more or less automatically bend, the end of the strut H sliding away from the block 1. Thus, the upper element A will collapse into its lowermost position so that flitting (i. e. movement from place to place of the machine while inoperative) is facilitated.

It will be appreciated that the adjustment means 1 to II is extremely simple to operate.

By Virtue of the invention, a machine provided with the shearing cutter can out under varying roof heights without requiring a different shearing cutter to be fitted.

In an alternative construction, the rear end of the adjustable strut H is adapted to be pinned directly to the element B instead of being fixed through the intermediary of a block such as 1.

I claim:

1. A mining machine shearing cutter of cutter chain type having a chain-guiding frame made up of a lower longitudinal element fixable to a mining machine, an upper longitudinal element pivotally attached to the rear of said lower element and a toggle linkage pivotally connected to the front of said lower and upper elements respectively, and means for varying the cutting height interposed between one of said elements and said toggle linkage, said interposed means being adjustable to bend more or less or to straighten said linkage and thus to lower or raise said upper element to a selected extent.

2. A mining machine with a shearing cutter of cutter chain type having a chain-guiding frame made up of a lower longitudinal element fixed to said machine, an upper longitudinal element pivotally attached to the rear of said lower element and a toggle linkage pivotally connected to the front of said lower and upper elements respectively, a sprocket on said machine for driving the cutter chain, means for adjusting said lower element in relation to said machine and sprocket in order to regulate the tension of the cutter chain, and means interposed between one of said elements and said toggle linkage, said interposed means being adjustable to bend or straighten said toggle linkage and thus to lower or raise said upper element without changing the regulated tension of the cutter chain.

3. A mining-machine shearing cutter of cutter chain type having a chain-guiding frame made up of a lower longitudinal element fixable to a mining machine, an upper longitudinal element pivotally attached to the rear of said lower element and a toggle linkage pivotally connected to the front of said lower and upper elements respectively, a strut pivotally connected to an element of said toggle linkage, and an adjustable abutment on one of said longitudinal elements, said strut being normally located against said abutment and thus serving to hold the toggle linkage in a setting which supports the upper longitudinal element at a selected height.

4a A mining-machine shearing cutter of cutter chain type having a chain-guiding frame providing a path for the cutter chain and made up of a lower longitudinal element, an upper longitudinal element pivotally connected at its rear end to the lower longitudinal element and toggle links interconnecting the front ends of the longitudinal elements, and means for vertically adjusting said upper element through a range of heights so as to vary the cutting height of the cutter and for simultaneously adjusting the angular relationship of said links so as to maintain constant the length of said path.

5. A mining machine with a shearing cutter of cutter chain type having a chain-guiding frame made up of a lower longitudinal element on the machine, an upper longitudinal element, a pivotal connection between the rear ends of said lower and upper longitudinal elements and a pair of toggle links pivotally connected to the front ends of the longitudinal elements, a sprocket on said machine for driving the cutter chain and providing in combination with said frame a path for the cutter chain, means for adjusting said lower element in relation to said machine and sprocket in order to regulate the cutter-chain tension by varying the length of said path, and means for vertically adjusting said upper element through a range of heights 50 as to vary the cutting height of the cutter and for adjusting the angular relationship of said links so as to maintain constant the length of said path.

6. A mining-machine shearing cutter including a frame which provides a path of guidance for an endless cutter chain, said frame compris ing a lower longitudinal element fixable to the body of a mining machine, an upper longitudinal element which is pivotally mounted at a rearward location on said lower longitudinal element for movement downwards and upwards to and from said lower element and a pair of pivotally interconnected toggle links the outer ends of which are pivotally connected to forward portions of said upper and lower elements respectively, and adjustment means for raising or lowering said upper element to vary the cutting height of said cutter and for simultaneously straightening or bending said toggle links to maintain constant the length of said path of guidance, said adjustment means comprising an abutment adjustably connected to one of said longitudinal elements and a strut pivotally connected to one of said toggle links and sliclably abutting against said abutment.

7. A mining-machine shearing cutter as claimed by claim 6 in which a chain-driving sprocket on the machine body cooperates with said frame to complete said path of guidance and said lower longitudinal element is lengthwise adjustable on the machine body to vary the length of said path in order to regulate the cutter-chain tension.

8. A mining-machine shearing cutter of cutter chain type having a chain-guiding frame made up of a lower longitudinal element which is fixable to a mining machine, an upper longitudinal element which can be raised or lowered to vary the height of cut and front linkage elements which interconnect said longitudinal elements, all of said elements being pivotally jointed together to make up a chain-guiding frame which forms an endless path of guidance for the chain and adjustment means for raising or lowering said upper longitudinal element about its pivotal joint with the lower longitudinal element through a range of positions and moving said linkage elements to neutralise any alteration in the length of the chain path due to the raising or lowering.

9. A mining-machine shearing cutter of cutter chain type having a chain-guiding frame made up of an upper longitudinal element and a lower longitudinal element which can be raised or lowered to vary the height of cut, said elements being in the same plane and being pivotal- 1y interconnected in the vicinity of their rear ends so as to be capable of opening and closing in that plane, and a front toggle linkage constituted of two other elements connecting the longitudinal elements at their forward ends, all of said elements individually forming parts of an endless path of guidance for the chain, and adjustment means for raising or lowering said upper longitudinal element through a range of positions and moving said linkage to neutralise any alteration in the length of the chain path due to the raising or lowering.

JOHN CONNEL SPROUL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,233,494 Morgan July 17, 1917 1,786,259 Osgood Dec. 23, 1930 

